1. Field of the Invention
The present invention relates generally to a sprayer. In particular, the present invention is concerned with a portable, operator-propelled research sprayer which is quickly assembled and easily adjusted to accommodate various spraying techniques.
2. Description of the Related Art
Agricultural sprayers are used to apply agricultural chemicals. Generally, sprayers fall into one of three categories: (1) hand-held sprayers, (2) tractor-mounted sprayers and (3) operator-propelled sprayers.
Hand-held sprayers may include a back pack frame and padded straps for carying the chemical containers and other major components of the sprayer. The operator manipulates a spray boom to apply the chemical to crops. With hand-held sprayers, it is difficult to maintain a constant speed to control the amount of chemicals applied to crops. Also, it is difficult for an operator to maintain a constant position of the spray boom. Furthermore, the operator may tire from the burden of carrying the sprayer.
Tractor-mounted sprayers are hitched to a tractor and include a frame mounted on wheels for supporting the sprayer, and in some instances, the operator. Generally, tractor-mounted sprayers are not suitable for use in narrow rows due to crop injury or small plots due to the difficulty of maintaining constant speed.
Operator-propelled sprayers generally include a frame for supporting the sprayer assembly and at least one wheel assembly. "Bicycle sprayers" have a pair of laterally-spaced large wheel assemblies and a caster positioned behind each of the large wheel assemblies. Drawbacks of bicycle sprayers include the fact the most bicycle sprayers can only be pushed, thus requiring the operator to walk through a sprayed area. Oftentimes and particularly in damp soil, the casters tend to dig into the ground, thereby requiring more effort by the operator to push the sprayer. Many bicycle sprayers are inadequate for tall crops.
Single wheel sprayers are operator-propelled, and as the name suggests, have a single wheel assembly. Such sprayers are also known as "wheelbarrow type" sprayers. Single wheel sprayers work generally on low crops only and are difficult to manipulate. Since part of the sprayer weight is carried by the operator, it is difficult to maintain a constant speed and at the same time prevent the sprayer from swaying.
Consequently, the art continues to seek improvements. It is desirable that an operator-propelled sprayer be pushed or pulled at a constant speed to ensure uniformity of chemical deposits. An improved operator-propelled sprayer should be easily adjustable to accommodate various crops and spraying techniques. It is desirable that a sprayer be easily balanced, portable and enable an operator to spray crops without walking through a sprayed area.